HMI, Berlin

Analytic results on level densities

Use of the free energy in dynamical fission calculations and of the level density in simultaneous particle-evaporation yields raises the question of compatibility of these two pieces of input in calculations of the decay of hot compound nuclei. Apparent discrepancies between the Bethe formula for the level density and the popular assumption of a quadratic temperature dependence of the free energy are discussed in the framework of the picket-fence model, where the theory of partitions allows to calculate all thermodynamic functions analytically together with their limits for large systems and high temperature.